Description

Vocabulary is a significant and frequently tested component of child language development. Standardized vocabulary measures are utilized by clinicians as well as researchers for a variety of purposes, and therefore it is important to recognize the strengths and weaknesses of such tools. Understanding the effectiveness of standardized measures is contingent on knowledge of their psychometric properties. This project reviewed the psychometric properties of 10 standardized vocabulary tests, chosen on the basis of their frequency of use, recency, and availability. Each selected test was then evaluated with regard to its normative sample (recency, size, and representativeness), reliability (internal consistency, test-retest reliability, inter-examiner reliability, and standard error of measure), and validity (developmental trends, comparison to similar tests, group comparisons, and sensitivity and specificity). Of the 10 tests, 4 met all criteria for the normative sample, while no test met each criterion in the areas of reliability or validity. Five tests, the MAVA, PPVT-4, EVT-2, EOWPVT, and ROWPVT, emerged as particularly strong measures, meeting the highest number of criteria. The area in need of the most improvement was that sensitivity and specificity, even though this is one of the most important indications of a test’s validity.
Results suggest that clinicians and investigators need to be aware of the psychometric properties of the tests they use, favoring those that are strongest for their specific purpose. However, even when psychometric properties are sound, there are inherent limitations in the function of standardized tests, and multiple forms of assessments are recommended, particularly for high-stakes evaluations.